dnsproject

Hey there,

Just noticed a weird thing yesterday on my 530dA. When hitting the floor @ 90km/h, everything is fine like it used to be, until it reaches around 125km/h / 3500 RPM. At this point, there's huge powerloss and it goes really slowly up after that.

Checked around on the forums and there have been similar cases, but not very identical it seems. Doesn't look like a turbo failure, because on lower speeds etc, the acceleration is all fine. Also acceleration at 90km/h & above it's fine, until it reaches that certain speed. Getting it to the dealers tomorrow, for diagnostics etc. Just wanted to hear 2nd opinion, before going there :-)

Thanks in advance!

Anzafin

My vote goes for a clogged diesel particulate filter (DPF).

A clogged DPF can be showed up via different symptoms, and this is one of them. When the DPF is clogged the backpressure after the turbo increases. It will affect the the turbo and the acceleration.
You can read more about the clogged DPF here: http://forums.5series.net/topic/94725...1#entry1120691

- Antti -

dnsproject

I got DPF checked at the dealers, few months ago. They replaced a temp sensor of the DPF.
Also checked the pressures, after that. All looked fine..
But gonna get it checked again tomorrow, definetly. Thanks for the input!

Anzafin

Or then it could be the brittled vacuum hoses that control the turbo (unless if it is electronically controlled).

- Antti -

sanjsanj

You need at least 75C for the dpf to regen properly.. Check the coolant is getting up to temperature (90C ON THE MOTORWAY) via the Secret OBC Menu, number 7. Calculate the unlock code by adding together the last 5 digits of your VIN.

http://www.scoopz.com/m5board/E60_Hi...structions.pdf

Ragtop Steve

Its the DPF, might need to be regenerated, Cleard out. Take the car for a run, get it up to tempreture, then find a nice road and rag the shit out of the car, this should clear the dpf valve, if it dont then your looking at a new one,,,,,,,,,Just delite it and have it coded out

dnsproject

I noticed this problem after having a 150km motorway trip the day before. I think it should have regenerated properly then.
The car warms up nicely to 90C, both thermostats have been replaced months ago aswell.
Will find out tomorrow @ the dealers..

dnsproject

Was indeed DPF clogged! Diagnosis read up several logs of 'DPF Heavily Clogged' errors. Getting it washed out currently.
Thanks for the tips everyone!

sanjsanj

Hmmm, why didn't it regen normally though?

dnsproject

No idea.. all the sensors of DPF are working fine, car also reaches the correct temp. I got swirlflaps removed year ago, but that's not the issue I guess?
About 3 months ago I had DPF temp sensor replaced. I guess until that time, it was not regenerating properly? And maybe there was too much soot already, to regenerate itself?
Just guessing..